A.27 library(nb_set): Non-backtrackable set
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Availability::- use_module(library(nb_set)).(can be autoloaded)
Sourceadd_nb_set(+Key, !Set)
Add Key to Set. If Key is already a member of Set, add_nb_set/3 succeeds without modifying Set.
ClioPatria (version V3.1.1-51-ga0b30a5)